Tool Pdf Info

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

The description clearly implies a read-only metadata retrieval operation and lists what the call reveals, which is useful. However, with no annotations provided, the description carries a heavier burden and does not explicitly state side-effect freedom, error behavior, or what happens with invalid/encrypted files.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is two short sentences with no fluff. It front-loads the operation and metadata fields, then adds the critical usage timing guidance. Every sentence earns its place.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a simple one-parameter metadata tool with an output schema present, the description is mostly complete: it says what the tool returns, when to call it, and what resource it operates on. Minor gaps are path semantics and edge-case behavior, already reflected in other dimensions.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The only parameter, 'path', has 0% schema description coverage, and the description does not explain the expected path format, file accessibility, or whether it must be a local file vs a URI. The phrase '任何 PDF' implies it is a path to a PDF, but the description fails to compensate for the bare schema.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description uses a specific verb ('获取') and a specific resource ('PDF 元信息'), and enumerates concrete metadata fields (page count, encryption, page size, title, author). It also distinguishes itself from the sibling PDF-processing tools by positioning itself as the pre-flight info tool.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

It explicitly states when to use it: '处理任何 PDF 前先调用此工具' (call this before processing any PDF). It does not explicitly name alternatives or when-not-to-use cases, but the pre-processing direction is clear enough for an agent to select it first.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.